This chapter assesses John Stuart Mill’s political philosophy, focusing on two particular features of his thought. First is Mill’s relation to the liberal political tradition. Second are his writings on race, gender, and empire, which have in recent years come into greater prominence. The chapter begins by highlighting Mill’s contributions to liberal political theory and utilitarian ethics, the two traditions of thought with which he’s most commonly associated. It then examines his views on government and democracy. The chapter also considers Mill’s views on human diversity and difference, showing how his treatments of race, empire, and gender intersect with his liberalism. Finally, it reflects on what we might think about his political philosophy in light of his imperialist entanglements.